How to make a pinhole lens from a coke can
Pinhole photography is photography at its most fundamental. Based on the camera obscure that came before it, the principle is essentially the same. The only real difference here is that there’s something to capture the image. In this case, the digital sensor of your mirrorless camera or DSLR.
In this video, Sean from Fotodiox walks us through making a pinhole lens. It’s a lens that pretty much any of us can make just for the cost of a can of coke – or your soda of choice. That’s because it’s made from the can itself, along with a bit of gaffer tape. It’s a pretty simple project to try.
The process, at its simplest, is pretty straightforward. All you need to do is remove the top of the can (the bit where the ring pull is), poke a hole in the bottom with a pin, and then gaffer tape it to a lens adapter to be able to mount it to your camera. Doing nothing more does technically give you a pinhole lens, but as you can see in the video above, it’s not perfect. The shiny metallic surface of the can’s interior allows the light to bounce around and cause all kinds of weird flare issues.
Sean overcomes this by covering the inside of the can with black gaffer tape. This helps to remove most of the reflections, although it’s a bit of a fiddly process, so you’re bound to have one or two gaps in there. This can also be seen in the video, with some very slight flare still visible under certain lighting conditions. Personally, I think I’d grab myself a can of matte black spray primer and coat the inside – probably the outside, too, just for aesthetics, even if not for functional reasons.
The complete coke can does present you with a pretty telephoto lens. After all, with pinhole cameras, the focal length is effectively the length of the “lens” from the film plane. If the two are 100mm apart, you have a 100mm lens.
If you want to bring it back a bit for a wider field of view, all you need to do is cut the can down. But again, don’t forget to make the inside black, or you’ll potentially have flare issues.
A cheap and easy lens you can make yourself!
John Aldred is a photographer with over 20 years of experience in the portrait and commercial worlds. He is based in Scotland and has been an early adopter – and occasional beta tester – of almost every digital imaging technology in that time. As well as his creative visual work, John uses 3D printing, electronics and programming to create his own photography and filmmaking tools and consults for a number of brands across the industry.